Genus and species are characteristics that determine every definition. However, they are not the only determining factors. These factors include the further moment of proprium and of differentia specifica as such. These aspects, which guide concept-formation, are called predicables or κατηγορήματα. These κατηγορήματα were systematically treated for the first time by Porphyry   in his introduction to Aristotle  ’s Κατηγορίαι. This Εἰσαγωγή was then translated into Latin by Boethius   and became the basic text on logical questions in the Middle Ages. The so-called controversy over universals of the Middle Ages developed in connection with this Εἰσαγωγή. There are five predicables:

1. Genus est unum, quod de pluribus specie differentibus in eo quod quid est praedicatur. “Curved, closed line”—the genus of the circle—is predicated of many things that are distinct in species (ellipse). Still, the predicate captures what the circle in itself is.

2. Species est unum, quod de pluribus solo numero differentibus in eo quod quid est praedicatur. The individual circle solo numero differunt.

3. Differentia specifica aut διαφορά est unum, quod de pluribus praedicatur in quale essentiale, “with respect to that which belongs to what they are,” such as the rationality of the human being.

4. Proprium est unum, quod de pluribus praedicatur in quale necessarium, a “necessary” determination that belongs to the thing, but also lies outside of the essential context of genus and species.

5. Accidens est unum, quod de pluribus praedicatur in quale contingens, insofar as that which is addressed is “haphazard” (συμβεβηκóς).14

These praedicabilia are also called universalia. The precise distinction consists in the fact that universale means: unum quod est in pluribus, as opposed to praedicabile: unum quod de pluribus praedicatur. Hence the question of whether the general actually exists in the things or is only the generality of apprehending thought (Realism—Nominalism). This question also has its origin in determinate concrete contexts of Greek philosophy, or better in scholastic misunderstandings thereof. [HEIDEGGER  , GA18:15-16]

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LÉXICO: predicável; categoremático